public class Example3_6 {
	public static void main(String args[]) {
		double sum=0,item=1;
		int i=1,n=20;
		while(i<=n) {
			sum=sum+item;
			i=i+1;
			item=item*(1.0/i);
		}
		System.out.println("sum="+sum);
	}
}
